1. Field of the Invention
This application claims priority from Korean Patent Application No. 2006-3536 filed Jan. 12, 2006, and Korean Patent Application No. 2007-2389 filed Jan. 9, 2007, each of which are incorporated by reference in their entireties.
The invention relates to a device for and a method of informing replacement time of an air filter, more particularly, to a device for and a method of informing replacement time of an air filter, in which the accumulation amount of the dust accumulated in the air filter is calculated based on the factors such as a contamination degree of the air introduced into the air filter, an air introduction time, and an air introduction volume, and then when the accumulation amount of the total dust in the air filter exceeds a reference value, a driver is informed of the replacement time of the air filter, so that it is possible to replace the air filter at an optimum instance to thereby maintain the pleasant interior circumstance of a vehicle, to prevent the dissipation of the expense caused by the unnecessary early replacement of the air filter, and to prevent the interior air contamination of the vehicle due to the delay of the replacement of the air filter, and the like.
2. Background of the Related Art
In general, an air conditioning device for a vehicle is designed to introduce exterior/interior air of the vehicle and heat or cool it to thereby blow the air into the interior of the vehicle, resulting in the heating or cooling of the vehicle interior. As shown in FIG. 1, the vehicle air conditioning device comprises a blower provided with an exterior/interior air switching door 10 at the inside for selectively opening and closing an interior/exterior air inlet opening formed at an inlet side according to an interior/exterior air mode, and a blower driven by a motor for blowing the air introduced through the interior/exterior air inlet opening to an air conditioning case; an evaporator and a heater core disposed at the inside of the air conditioning case with a predetermined interval there-between; a temperature control door disposed between the evaporator and the heater core for controlling the volume of the air passing through the heater core; a mode door disposed at an outlet side of the air conditioning case for opening and closing a plurality of vents communicating with the interior of the vehicle; and an air filter disposed at the upstream of the blower.
Accordingly, if the user operates a predetermined operation unit 30 for controlling the air conditioning device, the control unit 28 selects the interior/exterior air conversion unit by controlling the position of the interior/exterior air switching door, controls the air introduction volume by controlling the blower motor or controls the positions of the temperature control door 20 and the mode door 24, or performs the temperature and various air conditioning modes.
In other words, in case of the interior air mode, the interior/exterior air switching door 23 is operated to open the interior air inlet opening 21 and close the exterior air inlet opening 22, and the interior air introduced through the interior air inlet opening 21 by means of the operation of the blower, passes through the air filter to be blown into the inside of the air conditioning case, and then it is introduced into respective vents with selectively passing through the heater core by means of the temperature control door and the mode door and is emitted into the inside of the vehicle.
In addition, in case of the exterior air mode, contrary to this operation, the interior/exterior air switching door 23 tightly closes the interior air inlet opening 21 and opens the exterior air inlet opening 22, and the exterior air introduced through the exterior air inlet opening 22 by means of the operation of the blower, passes through the air filter to be blown into the inside of the air conditioning case, and then it is introduced into respective vents with selectively passing through the heater core by means of the temperature control door and the mode door and is emitted into the inside of the vehicle.
In this regard, the air filter 16 disposed at the air conditioning device is operated to filter out the dust in the air to purify the air introduced through the interior/exterior air inlet openings. However, if it is used for a long time, the dust is concentrated to thereby increase the resistance of the air passing through the air filter 16 rapidly and cause the pollution of the air, so that it is necessary to change the air filter at a proper instance.
With regard to a conventional technology for exchanging the air filter at a proper time, there was disclosed a Korean Patent Application Laid Open No. 10-1996-0023728, in which a device for detecting the replacement time of the air filter was suggested. Referring now to FIGS. 2 and 3, the device for detecting the replacement time of the air filter is characterized by further comprising a blower motor driving means 46 for driving a blower motor of a blower, driving means 48 of suction air selection means disposed for the blower to suck the exterior air or the interior air selectively, display means 40 or alarming means 42 for informing the replacement time of the filter means, and control means for counting the driving time of the driving means 48 of the suction air selection means and the blower motor driving means 46 and informing the replacement time of the filter means to the alarming means, in addition to the vehicle air conditioning device with a filter, which includes a blower for blowing interior air or exterior air of a vehicle, an evaporator unit connected to an emitting opening of the blower.
Also, there was disclosed a method for detecting the replacement time of an air filter in an air conditioning device for a vehicle with filter, which is provided with a blower for blowing interior air or exterior air in a vehicle, an evaporator unit connected to an emitting opening of the blower, and filter means disposed at the inlet side of the evaporator unit, the method is characterized by comprising: a step S10 of accumulatively counting driving time of the blower, and a time for introducing the exterior air, a step S20 of determining whether or not the accumulative count time exceeds the respective predetermined exchange period by comparing the accumulatively counted driving time of the blower with a proper exchange period of the air filter predetermined after the driving of the blower, or comparing the accumulatively counted exterior air introduction time with a proper exchange period of the air filter after the driving of the blower, and a step S30 of informing the replacement time of the air filter or producing an alarming sound when any one of the two determinations exceeds the exchange period.
In other words, the conventional technique was directed to the detection of the replacement time of the air filter by comparing only the driving means of the suction air selecting means (holding time of the exterior air mode) and the blower motor driving means (blowing time) with the filter exchange period. Also, another conventional technique, which was disclosed in Korea Patent Laid Open No. 10-1996-0004754, was constructed to detect the replacement time of the air filter by sensing the speed of the blower motor, the load and the overload of the motor.
However, the conventional techniques have a problem that it was difficult to exchange the air filter accurately because they informed the replacement time regardless of the real amount of the dust accumulated in the air filter. In other words, since the accuracy of the replacement time of the air filter was reduced by the outer disturbing factors such as the difference of the pollution according to the driving area, and the overload due to the deterioration of the blower motor itself, and the like, there occurred problems that expense dissipation was caused due to unnecessary early exchange of the air filter and the occurrence of the air pollution in the vehicle due to delay of the exchange of the air filter.